The present invention relates to a new and distinct cultivar of apple tree, Geneva 65, which we discovered in a test planting belonging to New York State Agricultural Experiment Station, Cornell University, `Geneva`, Ontario County, N.Y. This discovery is a product of the apple rootstock breeding program of the New York State Agricultural Experiment Station (`Station`).
In 1974, pollen was collected from a Beauty Crab apple tree and used to pollinate emasculated flowers of a Malling 27 (M.27) apple tree growing on Station grounds. The seeds were harvested from fruit produced from this cross and were stratified in November, 1974. After stratification, 198 germinating seeds were planted in a Station greenhouse in January, 1975. When the emerging seedlings were about 2.5 cm tall, we inoculated the soil with zoospores of 13 isolates of the fungus Phytophthora cactorum which is the causal agent of crown rot. The flat was flooded to mid-hypocotyl level of the seedlings, and kept at about 23.degree. C. for 7 days. All but 54 of the 198 seedlings were killed by this process. The surviving seedlings, when 10 to 15 cm tall, were inoculated in their shoot tips with about 10.sup.6 cells of isolate Ea273 of the bacterium Erwinia amylovora, the causal agent of the of the fire blight disease, using a 26 -gauge hypodermic syringe. Four subsequent inoculations with E. amylovora isolate Ea273 were made.
We selected 5 Erwinia amylovora-resistant seedlings and planted them as trench layers on the Station's Loomis Farm in April, 1976. Rooted liners were harvested in late fall 1979, 1980 and 1981 and were planted in the Station nursery in the springs of 1980, 1981 and 1982 respectively. Maiden trees of the cultivars `Northern Spy`, `Red Spy`, `Golden Delicious`, `Topred Delicious`, `Summerland McIntosh` and `Mutsu` were produced by budding onto `Geneva 65` liners. These trees were subsequently planted in trial orchards at the Station and at the United States Department of Agriculture Appalachian Fruit Research Station, Kearneysville, W.Va.; Hilltop Orchards, Hartford, Mich.; and Highmoor Farm, University of Maine, Monmouth, Me.
In these test plantings, trees on `Geneva 65` were about 20% smaller than trees on the Malling 9 rootstock, based on comparison with the check trees in the same test plantings. Trees on `Geneva 65` began flowering very early, usually the second year in the orchard; which was especially noteworthy for `Northern Spy` and `Red Spy` cultivars, which at Geneva, N.Y., normally begin fruiting in the 5th or 6th year on the precocity-inducing rootstock Malling-Merton 106. All of the cultivars that have been tested on `Geneva 65` have demonstrated high production efficiency, equal to that experienced with the Malling 9 rootstock.